1. Field of the Invention
The invention relates to motion transmitting and speed reduction devices and more particularly to a speed reducer.
2. Description of Related Art
A conventional speed reducer is comprised of a casing, a high speed shaft connecting to an eccentric rod having a plurality of different, hollow pinion rollers, a plurality of low speed shaft pins rotatably disposed in the pinion rollers respectively and each having one end opposite to the high speed shaft and connected to the low speed shaft, a gear roller retaining ring mounted on the pinion rollers for confining the pinion rollers, and a plurality of ring gear pins each enveloped with a ring gear roller for rotatably engaging with the hollow pinion rollers and each having both ends connecting to an inner surface of the casing. Rotation of the eccentric rod rotates the pinion rollers about the ring gear pins to actuate the low speed shaft pins so as to rotate in the pinion rollers for speed reduction.
However, the conventional speed reducer is disadvantageous due to complicated construction, bulkiness, low efficiency, and high manufacturing cost. Thus, the need for improvement still exists.